Nemiana simplex were found in Vendian deposits of Transnistria a hundred years ago. They are present in layers with determined age of 557 million. There are fourteen places with such fossils in the world. Nemiana simplex are the markers of all deposits of the Yampilian layers of the Vendian. We need to take a closer look at the Nemiana simplex analysis, as their exact nature has not been determined so far. They were considered to be raindrops, jellyfish or polyps, which is not justified. The large fluctuations in their size, and the peculiarities of their location relative to each other, indicate their biological nature. Usually, these fossils have the appearance of convex lenticular projections on the lower surfaces of sandstone layers 1-40 mm in size. They do not have any signs of the mouth opening and any other structural elements of the intestinal cavity. There are similar Nemiana prints of Beltanella and Beltanelliformis. Beltanelliformis has recently been recognized as "benthic colonies of cyanobacteria" by organic petrified films, sometimes preserved on their prints. Nemiana's prints do not contain such petrified films on the surface of the nuclei, so one cannot ascertain from biochemical analysis what they were during lifetime. Nemiana is not similar to Beltanelliformis: the distinctive features of Beltanelliformis are the absence of pronounced convex casts and concentric folds along the contour of flat prints. Although there are differences in the shape of the prints, Beltanelliformis and Nemiana are the most similar among the Vendian fossils. Given that Beltanelliformis are reflections of cyanodacetrians, we can assume that Nemiana is also a cyanobacterium. The print sizes of Nemiana simplex Palij are close to the size of modern spherical colonies of cyanobacteria Nostoc prunum. Large colonies of modern Nostoc prunum are often surrounded by smaller colonies, and in Nemiana simplex prints large prints together with smaller ones create a "cluster". Such clusters consist of entire "settlements". Nostoc colonies can appear very close to the main colony, creating "kidneys", with Nemiana simplex prints showing such "buds". Colonies of Nostoc cyanobacteria are widespread in fresh water, less often in the seas; Nemiana is found in deposits of huge deltas, that is, also in significantly desalinated seawater. It is likely that such Nostoc forms existed earlier than 550 million years ago and are still preserved in the Nemiana simplex prints on the Yampilian sandstones. Nemiana simplex prints are found on all modern continents, which indicates the conjugacy of the sea basins and the homogeneous climatic conditions on the planet during the Upper Vendee. The restoration of "settlements" of Nemiana simplex, which were systematically covered with sandy sediments, indicates their high ability to survive and the variability of reproduction.
The structure, strength properties, and dynamics of release of the drug on polymer carriers were investigated.
The article presents the results of a study of coenopopulations of European relict species, regionally rare ornamental spring ephemeroid Isopyrum thalictroides L. in the collection “Rare plants of the flora of Ukraine” and botanical-geographical areas “Altai and Western Siberia” and “Steppes of Ukraine” of M. M. Gryshko National Botanical Garden of the National Academy of Sciences of Ukraine (NBG). The origin of I. thalictroides in the areas of the NBG is different. On the plot “Rare plants of the flora of Ukraine” I. thalictroides is an introduced species, but in the areas “Altai and Western Siberia” and “Steppes of Ukraine” it is ergasiophygophyte. In the areas of NBG I. thalictroides shows a tendency to expand the territory, penetrates into forest (“Altai and Western Siberia”) and meadow-steppe (“Steppes of Ukraine”) cultural phytocoenoses, where it forms spontaneous coenopopulations. The conditions of habitats and sizes of coenopopulations of I. thalictroides differ in the areas of NBG: the largest is in the area “Rare plants of flora of Ukraine” (2.6 × 2.6 m), medium in “Altai and Western Siberia” (sizes of loci 1.3 × 1.3 m, 0.4 × 0.4 m and 0.1 × 0.1 m), the smallest in “Steppes of Ukraine” (0.3 × 0.3 m). Rhythms of growth and development of I. thalictroides in the conditions of Kyiv quite correspond to seasonal fluctuations of temperatures. The earliest flowering of I. thalictroides was observed in the areas of the NBG in the first half of April 2020, the latest in the second half of April in 2021–2022; flowering period in the beginning of fruiting in all areas coincided. Coenotic conditions of I. thalictroides habitats in the composition of artificially formed vegetation in the NBG and in nature differ. In the NBG areas, the species grows together with introduced, native and alien plant species and shows significant ecological and coenotic plasticity. The age spectra of all coenopopulations of I. thalictroides on the NBG areas are left-handed. The total percentage of shoots of the pregenerative period of ontogenesis (juvenile, immature, virginіle) is very high (88.98–93.62 %). The highest values are for virginile shoots (71.78–82.98 %), which may be due to the predominance of vegetative propagation over seed. The spatial distribution of shoots in coenopopulations of I. thalictroides is group, which may be due to a combination of barochoria and vegetative propagation. The number of shoots in coenopopulations of I. thalictroides in different parts of the NBG differs significantly: the largest is in the area “Rare plants of flora of Ukraine” (3562 shoots), medium in “Altai and Western Siberia” (1017 shoots), the smallest in “Steppes of Ukraine” (47 shoots). In contrast, the average density of shoots in all coenopopulations of I. thalictroides is high, uniform and is 522–546 different age shoots per 1 m2. The dependence of the number of flowers and/or fruits оn generative shoots from the height of the shoots was not detected. A study of the growth and development of I. thalictroides in NBG areas has shown that the formation of coenopopulations, both introductory and spontaneous, is an effective and promising method of conservation and protection of this species ex situ.
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